The Worthington advance. [volume] (Worthington, Minn.) 1874-1908, 1887-03-03
Testing Limestone.

Deposits of excellent limestone often
exist in portions of the country that
have long been settled, but their value
for making quick-lime is not deter.
mined. If the stone resembles in col.
or and texture that used for making
lime in a part of the country from
which any of the settlers came, some
one generally makes a kiln and pre-.
pares qmck-lime for the market. If it
has different color and texture. the
chances arc that it will not be utilized
for MANY years. During all this time
the people in the vicinity pay high
prices tor lime on account OF the en-
pense OF transporting it, and often suf-
fer great Inconvenience in not being
able to obtain a supply when they have
occasion TO use it. Until the late civil
war lime made at the Maine penten.
tiary. at Rockland, was used for max.
ing mortar to be used IN the erection
OF buildings IN towns in Arkansas; al
though the state is most bount!fully
supplied with most excellent limestone,
stone; and fire clay suitable for the
erection of kilns. and the best of fuel:
Much OF this stone was black or nearly
pure white, aud the people doubtless
]y thought that gray was the color
which stone should have that would
produce good article of lime. Lime
stone is a carbonate of lime, and exists
in great variety of forms. Marble,
whether white. black, mottled, or va
riegated. is nearly pure carbonate
OF lime. Common chalk is a peculiar
form OF limestone, very common on
the south coast of England, but quite
rare in this country: A large proper
ton of the limestone found in the west:
ern states and territories is quite com.
pact and of gray color. The color is
due to mineral OF vegetable impurities.
Detached stones found on the surface
OF the ground or thrown up by blowing
generally Indicate the presence of a
large deposit in the vicinity. They may,
however, have been broug ht from quito
a distance by the water Or some other
agency: Available deposits of lime
stone do not always crop out of the
ground or show themselves upon the
surface. They are often found several
feet below the surface in digging wells
or making bitches for tho purpose of
draining low land. A very valuable de-
post of limestone was recently found
in Champaign county, Illinois. while
workmen were engaged in draining d
bog: l. mestone can often be quarried
to good advantage if it is several feet
below the surface. It is. no objection
to the stone for making lime that it is
moist. The presence of moisture in it
appears to felicitate the driving off Of
the carbonic acid, which IS necessary
for converting the stone into quick
lime, or the lime of commerce: This
acid, which ordinarily exists in the
form of a gas, does not form q very
strong union with the lime base 1t
can readily be displaced by the use of
any of the common acids: Common
vinegar, which is very dilute acetic acid.
will, if poured on p'cce of limestone,
cause the carbonic acid to escape. The
vinegar will appear to fail, owing to
the escape of the bubbles of gas
through it. If gas escapes from a
piece of stone to which vinegar has been
applied, the evidence is nearly conclu-
sive that it is carbonate Of lime. 10
test it furthur it is only necessary to
place piece of stone as large as a
hens egg in a blacksmith s. forge or
upon wood fire or stove where hard
coal or wood is burned. and allow it to
remain five or six hours. II at the end
of that time it will ''slake" the experi-
menter may be assured that the stone
will make quick lime. BY burning
several pieces in this way ''slaking,"
mixing sand with them. and making
morter in the usual way, tho
value of this lime can be compared
with that in the market. - chicago